One modifiable risk factor for obesity that has received considerably little, if any, attention is sleep. However, recent studies in children and adults have shown that total amount of sleep is inversely associated with body mass index (BMI), an observation not well characterized in adolescents. Sleep/wake disruption has the potential to impact selected endocrine systems and metabolic paths that can cause changes in hunger and satiety, promoting excess eating and leading to obesity. Because of the high prevalence of both obesity and compromised sleep in this group, the purpose of this study is to explore associations among sleep/wake disruption, hunger, satiety, and BMI in a group normal of weight, at risk for overweight, and overweight adolescents 14-18 years old. Subjects will complete the Pittsburgh Sleep Quality Index, Pediatric Daytime Sleepiness Scale, wear a wrist actigraph, and record a sleep, hunger, and satiety diary for eight days. The results of the work will provide valuable data on sleep and hunger. This study has the potential to enhance clinical practice through the translation of basic science concepts into the development and testing of innovative interventions that may subsequently help to improve sleep and decrease adolescent obesity. [unreadable] [unreadable] [unreadable]